gene transcription occurs in fertilized eggs of the amphibian Xenopus til the mid-blastula transition, (approximately 4000 cells). Therefore, l of the appropriate gene products necessary for early development must ve been stored prior to fertilization in the oocyte or egg. In order to derstand the molecular embryology of early amphibian development, it will necessary to obtain genes whose products are expressed only in oocytes. ile working as a post-doctoral fellow with John Gurdon in Cambridge, gland, I discovered a gene which is transcribed only in the oocytes of nopus. This gene is called OAX for oocyte activated in Xenopus, and codes r a previously unreported 181 nucleotide long RNA. The OAX RNA sequence ntains 2 elements which fit the RNA polymerase III promoter consensus quence. There are approximately 10,000 copies of OAX RNA per oocyte and e RNA appears to be present in a cytoplasmic complex of approximately 50S ze. OAX RNA persists until at least gastrulation, but no OAX RNA can be und in adult somatic tissues.